Sky-Watcher 10" Flextube Dobsonian Telescope

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Please note: Due to high shipping costs and low profit margins on this item, we might ship this from our stock or have the manufacturer drop ship this item to you.
- If this page lists the item as "In Stock", your order will ship within 3 days either from us or from the manufacturer.
- If this page lists the item as "Back Order" or "Drop Ship", it will be drop shipped from the manufacturer subject to their availability. In case of any delays for back-ordered or drop-shipped items, we will contact you promptly and update you on its status. Or you can contact us first and we can get you a shipping estimate before you order.
- Large 250mm aperture delivers stunning viewing experience
- Innovative collapsible design that retains collimation
- 1235x more light-gathering power than the human eye
- Patented tension control handle allows for precise slewing and maximum stability
- Parabolic primary mirror with Radiantâ„¢ Aluminum Quartz (RAQâ„¢) coating for 94% light reflectivity
- Heavy-duty rocker box with Teflonâ„¢ bearings provide a stable base with smooth motion
- 2-inch Crayford-style focuser with 1.25-inch adapter allows for use of nearly any eyepiece
For decades, the Dobsonian stood as a DIY staple of amateur astronomy, usually constructed with two mirrors, a tube and a base. Often referred to as ‘light buckets’, Dobsonians provide users with the highest possible aperture for their money when compared to telescopes of a similar size, such as Schmidt-Cassegrains or refractors. Developed in the 1970s, the Dobsonian-style telescope is an inexpensive solution for bright, detailed visual observing using a simple design. The name ‘Dobsonian’ comes from the telescope’s inventor, John Dobson, a Vedanta monk who popularized sidewalk astronomy and dedicated his life to astronomy outreach. Dobson was well known for constructing large aperture reflecting telescopes capable of deep sky viewing, using low cost materials. These were often made with found materials, heavy cardboard tubes, recycled porthole glass, and plywood mounts. Dobson, who literally wrote the book on how and why to make amateur telescopes, encouraged other astronomers to assemble their own telescopes and taught workshops on telescope making.
The Sky-Watcher Flextube 250P Collapsible Dobsonian # S11720 innovates on that original design, offering users the ability to collapse the optical tube using a proprietary truss-tube system while retaining its collimation. The optical tube uses a parabolic primary mirror, constructed of borosilicate, then polished and coated with our proprietary Radiantâ„¢ Aluminum Quartz (RAQâ„¢), producing a remarkable 94% reflectivity. With a 10-inch aperture, the Flextube 250P Dobsonian collects 1235 times more light than the human eye! This simple yet effective design is perfect for visual observation of faint objects, such as nebulae, star clusters, and galaxies.
Supporting the Flextube Dobsonian is more than just a simple rocker box. The base uses Teflonâ„¢ bearings for smooth, easy Azimuth slewing and a patented tension control handle to lock the telescope in place. Once locked on an object, the telescope can support both 1.25-inch eyepieces as well as the heavier 2-inch eyepieces, allowing you to use virtually any eyepiece on the market. All Flextube Dobsonians come with a slew of accessories, including: two 1.25-inch eyepieces, a 1.25-inch eyepiece adapter, a 2-inch eyepiece adapter, dust caps, and a 8x50 finderscope.
At Sky-Watcher, we stay true to the traditional John Dobson design, while offering a fresh look for the 21st century. Although we love computerized telescopes, using a star chart to find objects by hand can be far more fulfilling and will improve your knowledge of the night sky. Unplug your electronic devices, step outside, and become immersed in the wonders of the universe.
Specifications:
Optical Info:
- Optical Design: Newtonian
- Mirror Coatings: Radiant Aluminum Quartz (RAQ)â„¢ coatings with 94% reflectivity
- Glass Type: Borosilicate
- True Aperture (mm): 257
- Primary Aperture (mm): 254
- F/Ratio: 4.7
- Focal Length (mm): 1200
- Secondary Diameter: 64mm
- Secondary Obstruction (by diameter): 25%
- Secondary Obstruction by Area: 6%
Observational Info:
- Dawes Limit: 0.46
- Rayleigh Limit 0.55
- Limiting Mag.: 14.5
- Minimum Magnification: 36
- Maximum Magnification: 500
- Light Gathering (compared to next size down): 57%
General Info:
- Focuser: 2" Crayford
- OTA Length (Retract/Ext.): 31.5"/44"
- OTA Outer Diameter: 11.375"
- OTA Weight (with accessories): 33
- Dob Base Weight: 26.5
- Dob Base Measurements: 29.5"x20"
- Zenith Eyepiece Height: 48"
Accessories:
- Included Finder: 8x50 RACI
- Included Diagonal: No
- Included Eyepieces: 25/10 Plossl
- Magnification w/ Included Eyepieces: 48x/120x
- Included Case: No
- Corrector: No
Other Information
- Country of Manufacture: China
For decades, the Dobsonian stood as a DIY staple of amateur astronomy, usually constructed with two mirrors, a tube and a base. Often referred to as ‘light buckets’, Dobsonians provide users with the highest possible aperture for their money when compared to telescopes of a similar size, such as Schmidt-Cassegrains or refractors. Developed in the 1970s, the Dobsonian-style telescope is an inexpensive solution for bright, detailed visual observing using a simple design. The name ‘Dobsonian’ comes from the telescope’s inventor, John Dobson, a Vedanta monk who popularized sidewalk astronomy and dedicated his life to astronomy outreach. Dobson was well known for constructing large aperture reflecting telescopes capable of deep sky viewing, using low cost materials. These were often made with found materials, heavy cardboard tubes, recycled porthole glass, and plywood mounts. Dobson, who literally wrote the book on how and why to make amateur telescopes, encouraged other astronomers to assemble their own telescopes and taught workshops on telescope making.
The Sky-Watcher Flextube 250P Collapsible Dobsonian # S11720 innovates on that original design, offering users the ability to collapse the optical tube using a proprietary truss-tube system while retaining its collimation. The optical tube uses a parabolic primary mirror, constructed of borosilicate, then polished and coated with our proprietary Radiantâ„¢ Aluminum Quartz (RAQâ„¢), producing a remarkable 94% reflectivity. With a 10-inch aperture, the Flextube 250P Dobsonian collects 1235 times more light than the human eye! This simple yet effective design is perfect for visual observation of faint objects, such as nebulae, star clusters, and galaxies.
Supporting the Flextube Dobsonian is more than just a simple rocker box. The base uses Teflonâ„¢ bearings for smooth, easy Azimuth slewing and a patented tension control handle to lock the telescope in place. Once locked on an object, the telescope can support both 1.25-inch eyepieces as well as the heavier 2-inch eyepieces, allowing you to use virtually any eyepiece on the market. All Flextube Dobsonians come with a slew of accessories, including: two 1.25-inch eyepieces, a 1.25-inch eyepiece adapter, a 2-inch eyepiece adapter, dust caps, and a 8x50 finderscope.
At Sky-Watcher, we stay true to the traditional John Dobson design, while offering a fresh look for the 21st century. Although we love computerized telescopes, using a star chart to find objects by hand can be far more fulfilling and will improve your knowledge of the night sky. Unplug your electronic devices, step outside, and become immersed in the wonders of the universe.
Specifications:
Optical Info:
- Optical Design: Newtonian
- Mirror Coatings: Radiant Aluminum Quartz (RAQ)â„¢ coatings with 94% reflectivity
- Glass Type: Borosilicate
- True Aperture (mm): 257
- Primary Aperture (mm): 254
- F/Ratio: 4.7
- Focal Length (mm): 1200
- Secondary Diameter: 64mm
- Secondary Obstruction (by diameter): 25%
- Secondary Obstruction by Area: 6%
Observational Info:
- Dawes Limit: 0.46
- Rayleigh Limit 0.55
- Limiting Mag.: 14.5
- Minimum Magnification: 36
- Maximum Magnification: 500
- Light Gathering (compared to next size down): 57%
General Info:
- Focuser: 2" Crayford
- OTA Length (Retract/Ext.): 31.5"/44"
- OTA Outer Diameter: 11.375"
- OTA Weight (with accessories): 33
- Dob Base Weight: 26.5
- Dob Base Measurements: 29.5"x20"
- Zenith Eyepiece Height: 48"
Accessories:
- Included Finder: 8x50 RACI
- Included Diagonal: No
- Included Eyepieces: 25/10 Plossl
- Magnification w/ Included Eyepieces: 48x/120x
- Included Case: No
- Corrector: No
| Free Shipping Graphic | Free Contiguous US Shipping |
|---|---|
| Telescope Focal Length | 1001 - 1250mm |
| Hide Found a better Shipped Price on Frontend? | No |
Please note: Due to high shipping costs and low profit margins on this item, we might ship this from our stock or have the manufacturer drop ship this item to you.
- If this page lists the item as "In Stock", your order will ship within 3 days either from us or from the manufacturer.
- If this page lists the item as "Back Order" or "Drop Ship", it will be drop shipped from the manufacturer subject to their availability. In case of any delays for back-ordered or drop-shipped items, we will contact you promptly and update you on its status. Or you can contact us first and we can get you a shipping estimate before you order.
- Large 250mm aperture delivers stunning viewing experience
- Innovative collapsible design that retains collimation
- 1235x more light-gathering power than the human eye
- Patented tension control handle allows for precise slewing and maximum stability
- Parabolic primary mirror with Radiantâ„¢ Aluminum Quartz (RAQâ„¢) coating for 94% light reflectivity
- Heavy-duty rocker box with Teflonâ„¢ bearings provide a stable base with smooth motion
- 2-inch Crayford-style focuser with 1.25-inch adapter allows for use of nearly any eyepiece
For decades, the Dobsonian stood as a DIY staple of amateur astronomy, usually constructed with two mirrors, a tube and a base. Often referred to as ‘light buckets’, Dobsonians provide users with the highest possible aperture for their money when compared to telescopes of a similar size, such as Schmidt-Cassegrains or refractors. Developed in the 1970s, the Dobsonian-style telescope is an inexpensive solution for bright, detailed visual observing using a simple design. The name ‘Dobsonian’ comes from the telescope’s inventor, John Dobson, a Vedanta monk who popularized sidewalk astronomy and dedicated his life to astronomy outreach. Dobson was well known for constructing large aperture reflecting telescopes capable of deep sky viewing, using low cost materials. These were often made with found materials, heavy cardboard tubes, recycled porthole glass, and plywood mounts. Dobson, who literally wrote the book on how and why to make amateur telescopes, encouraged other astronomers to assemble their own telescopes and taught workshops on telescope making.
The Sky-Watcher Flextube 250P Collapsible Dobsonian # S11720 innovates on that original design, offering users the ability to collapse the optical tube using a proprietary truss-tube system while retaining its collimation. The optical tube uses a parabolic primary mirror, constructed of borosilicate, then polished and coated with our proprietary Radiantâ„¢ Aluminum Quartz (RAQâ„¢), producing a remarkable 94% reflectivity. With a 10-inch aperture, the Flextube 250P Dobsonian collects 1235 times more light than the human eye! This simple yet effective design is perfect for visual observation of faint objects, such as nebulae, star clusters, and galaxies.
Supporting the Flextube Dobsonian is more than just a simple rocker box. The base uses Teflonâ„¢ bearings for smooth, easy Azimuth slewing and a patented tension control handle to lock the telescope in place. Once locked on an object, the telescope can support both 1.25-inch eyepieces as well as the heavier 2-inch eyepieces, allowing you to use virtually any eyepiece on the market. All Flextube Dobsonians come with a slew of accessories, including: two 1.25-inch eyepieces, a 1.25-inch eyepiece adapter, a 2-inch eyepiece adapter, dust caps, and a 8x50 finderscope.
At Sky-Watcher, we stay true to the traditional John Dobson design, while offering a fresh look for the 21st century. Although we love computerized telescopes, using a star chart to find objects by hand can be far more fulfilling and will improve your knowledge of the night sky. Unplug your electronic devices, step outside, and become immersed in the wonders of the universe.
Specifications:
Optical Info:
- Optical Design: Newtonian
- Mirror Coatings: Radiant Aluminum Quartz (RAQ)â„¢ coatings with 94% reflectivity
- Glass Type: Borosilicate
- True Aperture (mm): 257
- Primary Aperture (mm): 254
- F/Ratio: 4.7
- Focal Length (mm): 1200
- Secondary Diameter: 64mm
- Secondary Obstruction (by diameter): 25%
- Secondary Obstruction by Area: 6%
Observational Info:
- Dawes Limit: 0.46
- Rayleigh Limit 0.55
- Limiting Mag.: 14.5
- Minimum Magnification: 36
- Maximum Magnification: 500
- Light Gathering (compared to next size down): 57%
General Info:
- Focuser: 2" Crayford
- OTA Length (Retract/Ext.): 31.5"/44"
- OTA Outer Diameter: 11.375"
- OTA Weight (with accessories): 33
- Dob Base Weight: 26.5
- Dob Base Measurements: 29.5"x20"
- Zenith Eyepiece Height: 48"
Accessories:
- Included Finder: 8x50 RACI
- Included Diagonal: No
- Included Eyepieces: 25/10 Plossl
- Magnification w/ Included Eyepieces: 48x/120x
- Included Case: No
- Corrector: No
Other Information
- Country of Manufacture: China
| Free Shipping Graphic | Free Contiguous US Shipping |
|---|---|
| Telescope Focal Length | 1001 - 1250mm |
| Hide Found a better Shipped Price on Frontend? | No |

Sky-Watcher 10" Flextube Dobsonian Telescope



















